c++/10261: g++ does not error for bogus |typename| inside a templated class

[bbaetz@acm.org]

>Number:         10261
>Category:       c++
>Synopsis:       g++ does not error for bogus |typename| inside a templated class
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    unassigned
>State:          open
>Class:          accepts-illegal
>Submitter-Id:   net
>Arrival-Date:   Sat Mar 29 01:56:00 UTC 2003
>Closed-Date:
>Last-Modified:
>Originator:     Bradley Baetz
>Release:        3.4 20030328 (experimental)
>Organization:
>Environment:
System: Linux mango.home 2.4.18-27.8.0custom #1 Thu Mar 20 20:14:56 EST 2003 i686 i686 i386 GNU/Linux
Architecture: i686

	
host: i686-pc-linux-gnu
build: i686-pc-linux-gnu
target: i686-pc-linux-gnu
configured with: ../gcc/configure --enable-languages=c,c++ --prefix=/home/bbaetz/swtest --program-suffix=-cvs --enable-__cxa_atexit
>Description:
g++ (3.2 and 3.4-cvs) accepts the use of the |typename| keyword even when 
the template is explicitly instatiated and does not have dependant 
parameters, if the use of this occurs from  within a template (see example 
below)

I'm not sure that this is a bug. I only have access to the draft c++ 
standard, but foo<int>::value_type doesn't depend on T, and the |baz| code 
is accepted without the typename also, even in 3.4.

MIPSPro 7.4 appears to disallow both cases, too - see
http://bugzilla.mozilla.org/show_bug.cgi?id=199625 (It also disallows
|typename| as a function param in a templated class, which I think is
incorrect although I'm not sure, so maybe its results should be taken with
a grain of salt...)

However, this appears to be handled by core issue 183
(http://anubis.dkuug.dk/jtc1/sc22/wg21/docs/cwg_defects.html#183) though,
which does make the use of |typename| illegal.

>How-To-Repeat:
template<typename T>
struct foo {
  typedef T value_type;
};

struct bar {
  typedef typename foo<int>::value_type t; //errors
  void xxx(typename foo<int>::value_type); //errors
};

template<typename T>
struct baz {
  typedef typename foo<int>::value_type t; //ok, but should be error
  void yyy(typename foo<int>::value_type); //ok, but should be error
};

>Fix:
	
>Release-Note:
>Audit-Trail:
>Unformatted: